Possible Rod bearing?!

[0range_240]

So when I had my car in the garage the other day, I had just finished replacing my pulley, and I hd some time so I decided to yank the stock intake resonator out... since then tho Ive been noticing a funny rattling or knocking sound almost, when I give the car gas anywhere from 3000-4500 rpm .. .. its not very loud, and I have to turn off the heater and my radio to hear it.. but its unnerving

I took the car to a local shop and they said it was a rod bearing, and that I should rebuild my motor for 1800 bucks.... but firstly im not gonna pay that much if I can do a swap later, and secondly I dont know if they are just pulling my leg so they can do more work on the car.

Is there any definitive way, besides yanking the motor and checking, to tell if a rod bearing is gone? I tried listening with a stethescope, but the noise seems to be quite uniform all over the motor, with it being clearest over the #2 cylinder on the valve cover on the intake side... if it was a rod bearing, where should I place the stethescope to listen for it? and what should it sound like?

when I listened to the side of the block, the knock sounded very distance and muffled.. HELP :wtc:

[nightwalker]

a rod bearing knock is pretty loud. You have to ask someone (other than a shop) who knows what it is. There are other things that could be making a sound. Make sure you have oil in the car, and make sure you timing chain is cool.

[ryan hagen]

yah, i check timing chain tensioners first, or have someone u know or that u can really trust check it out.

[0range_240]

well I had checked the timing chain when I had the valve cover off before, this was less than 200 kilometres ago, and both tensioners were there, and both were in good shape, and the chain seemed tight so...

Its so hard to find people or places you can trust these days... :down:

[Gladman]

just drive around for a few more days....

if it is infact a rod bearing, it will get LOUD before anything breaks...

rod bearings sound like a jackhammer is hitting the side of your block at full tilt, its not quiet at all.

[0range_240]

well the noise has in fact been there for about a week

and so far, it hasnt gotten quiter or louder as far as I can tell

[ryan hagen]

u could change your oil see if you see anything in it, and put some lucas oil stabilizer in and see if it get quiter?

[Bone]

I have a very similiar noise almost sounds like valve rattle only its muffled. Mine eases upo some once its warm but is alot worse when its cold. Mine is either a cracked Piston or a wrist pin. I wrap mine up to 7000rpm constantly and drive it like I stole it. This is the second 240 I have owned that has had the noise So I am assuming it is a wrist pin. Since both cars have ran strong and long with the noise. Maybe its the same deal with yours. I'm driving mine till she blows! Hope that helps. For the record I have been told numerous times mines a rod to but its not. I have done a crank kit and timing chain and it made no difference. hope this helps.

[INeedNewTires]

yea if its a bearing it will quiet down with that lucas oil stabalizer. also, when it warms up it gets worse, because the oil thins out and provides less protection. try letting the motor sit for a day or 2 and then start it up with your head in the engine bay, see if it starts knocking and then quiets down after a few seconds, then gets louder as it warms up. if so then its a bearing but if not then its something else. i dont know what a wrist pin sounds like so i cant comment on that.

[leespipedreams]

Get your car hot. Then change the oil filter. Then start car. dont give any gas. this will give you no oil pressure for a few sec.' and you will hear a bad rod knocking if you have one. Lee

[Turbozx]

A bad rod bearing can be quiet and barely noticeable - I could just faintly hear it. I know as it happened to me. You do not have to pull the motor out to check. With the engine in, you can lower the crossmember, remove the oil pan and check remove the bearings and then check them. My friend inspected and replace mine this way on his lift in his shop, but you can jack the car up high enough and put it on jackstands and do it.

Glenn